Former Labour TD Joe Costello has discontinued his action against the Oireachtas, the Minister for Housing, Planning and Local Government and the Attorney General over constituency revisions.

Mr Costello began his action last month, when it seemed as if a general election was imminent.

He wanted declarations that members of the Oireachtas had failed in their obligations to ensure constituencies are revised to take account of changes in population in the 2016 Census.

He said that if an election was called before legislation was enacted to deal with this issue, the makeup of the next Dáil would be in breach of the Constitution, which he described this as "an appalling vista".

However, he told the High Court today he was discontinuing his action as legislation to give effect to the boundary changes had now passed through all stages in the Dáil and Seanad.

He said all that now remained was the signature of the President for the Electoral (Amendment) (Dáil Constituencies) Bill 2017 to become law.

Mr Costello said High Court President Mr Justice Peter Kelly had adjourned proceedings to allow time for the Oireachtas to enact the necessary legislation urgently. 

He said he wanted to thank Mr Justice Kelly for his care and diligence and all concerned for dealing with the Bill so expeditiously.

The Labour spokesperson on Urban Regeneration said the appalling vista of constitutional vulnerability in the event of an early election before constituency boundaries had been adjusted, had been averted.

But he said much still needed to be done to implement the legislation and ensure full protection for the Constitution was in place.

He said if this work was not done, an election in January or February next year could still be problematic.

And he urged the minister to direct and resource local authorities around the country to carry out this work, including drawing up new registers of electors, redrawing constituency boundaries and adjusting polling stations, to ensure there was no new challenge to the Constitution.

Mr Costello's own former constituency of Dublin Central is due to be affected by the boundary revisions.

He lost his seat in the last election when it was reduced from a four-seater to a three-seater.

But the Constituency Boundary Commission recommended increasing it to four seats again.